The 13 Dinosaurs of Halloween (Part 2)

The 13 Dinosaurs of Halloween (Part 2)

by Dalek627711
Head of Paleo Research at the DPGPRC

It’s time! It’s time for the big giveaway! All you Jack O’ Lanterns, Skeletons and Witches out there… put on your special masks and watch the magic pumpkin!

Watch! Watch!

So we’ve gone through the first eight scary, creepy, or just plain weird dinosaurs in the countdown last time, now it’s time for the top five! Out of the pool of candidates, these made the top ranking!

So let’s get started with:

5. Zuul Crurivistator

“There is no Dalek, only ZUUUUUULL!”

No, all kidding aside, though… This dino earned its spooky name. It even sort of resembles Zuul from the first Ghostbusters film.

Found recently in Montana, this Ankylosaur was found to have the most intact skin preservation ever found on any dinosaur remains! It was given the creepy name in honor of the 1984 film “Ghostbusters”, and even though it probably wasn’t very scary looking, it could put the fear of Gozer into any carnivore that tried to eat it. Its name literally means “Zuul, Destroyer of Shins”.

“Who ya gonna call?”

4. Segnosaurs (The Mesozoic Edward Scissorhands)

Segnosaurs were always the biggest mystery in Paleontology until recently, when they were revealed to be the strangest theropods to ever have lived! Therizinosaurus, Erlikosaurus, Nothronychus, Segnosaurus, and even the very odd looking Deinocheirus were all actually HERBIVORES.

So how does a theropod go from a carnivorous lifestyle to one of a gentle vegan? It’s like this: competition among predator species is always a dominant factor in the balance of any biome. To survive, some species must adapt, and evolve - but these changes aren’t always what one would expect. Segnosaurs developed this plant-eating lifestyle because in the regions where they lived, the predator populations were starting to become more overcrowded than normal. So to eke out a living, they turned to herbivory. Not the most perfect of adaptations, as doing so meant that they would soon be on the menu. But evolution gave them a more than adequate defense: long, scythe-like claws (3 feet long) on each hand at the end of 6‘6“ arms was more than enough to give any predator that attacked it a VERY bad day. It could also be used to pull vegetation down to be eaten, sort of the way the modern-day sloth uses its clawed forelimbs.

The first to be discovered was actually Therizinosaurus, and it was the claws and forelimbs they found. The scientists who discovered it in Mongolia back in 1948 thought they were possibly the forelimbs of a new species of prehistoric turtle. Other discoveries in the 50s led scientists to the conclusion that this was a new species of dinosaur. In the 70s, a Russian scientist argued that it was actually an insectivore, using its claws to dig up termite mounds, sort of a giant bipedal anteater. He was right in that it was a theropod, but wrong in that it could survive on tiny insects. To science in the 70s though, this creature was enough of a mystery to still be considered a carnivore, based on the only fossils found, the giant claws. All this changed in 1973, with the discovery of the smaller and earlier ancestor of Therizinosaurus, Segnosaurus. It had a scaled-down appearance, but with a more complete skeleton, including a skull with leaf-shaped teeth and beak, they knew that this was no carnivore.


Deinocheirus seems to be the largest species in this group, and also the oddest looking. It had a hadrosaur-like snout, and a massive hump on its back, making it look more like a “Dino-Quasimodo” than anything else.

_“Sanctuaryyyyy…. Sanctuaryyyy….”

3. Carnotaurus Sastrei


Ah yes, the “Flesh-Eating Bull”. Found in Argentina back in 1984, This Abelisaurid was not only possessed of “devilishly” good looks, but it had speed to boot. It is estimated that if Carnotaurus took off in pursuit of prey at top speed, it would hit 35-40 mph. This is explained by its anatomy - in particular, a muscle at the base of its tail that acted like an aircraft carrier catapult. This is known as a caudofemoralis, and attached at the base of the tail, connecting to the thigh muscles. In Carno, however, it was MUCH thicker than in other carnosaurs, giving this predator explosive speed.


Like most Abelisaurs, Carno didn’t have much in the way of biting strength, and had small teeth. To bring down prey, Carnotaurus basically turned itself into a nuclear-powered battering ram, knocking prey animals down and using its thick neck muscles to whip the open mouth forward on impact, like an axe coming down hard. Prey usually died from a combination of shock, impact trauma, and blood loss.


Lots of other carnosaurs used this tactic, such as the Allosaurs, Carcharodontosaurs, and other theropods with a weak jaw, but Carnotaurus perfected the technique. It even one-upped the competition by doing so with no working arms to grab prey with! The Abelisaurs were unique in that during their evolution, we start to see that their arms and hands basically withered away to little floppy nubs. Carnotaurus’ arms were so stunted that they were basically just the upper arm bones and a hand. No wrists, no elbows. Scientists speculate that they may have had some sort of use, though, such as being held outward from the body to intimidate rivals, or attract a mate.


Also, this was one of the first dinos found to have lots of fossilized skin impressions along with the skeletons found, giving us a better understanding of what dino skin looked like.

2. Spinosaurs (The Mesozoic Freddy Kruegers)

Spinosaurus Aegyptiacus… Irritator Challengeri… Baryonyx Walkeri… Suchomimus Tenerensis… The names evoke fear and dread. Like Freddy the K, they stalk our nightmares with their massive claws and huge teeth in long crocodile-like jaws, striking out to draw blood…

But in reality, they all shared the same trait - an oddity for theropods - they were all mainly ichthyophagous (fish-eaters). Evolution had granted them the means to be successful in a riverine or estuarine environment, possibly going so far as to grant them the ability to be decent swimmers, to boot!

Of all of the members of this family, Spinosaurus is probably the least understood, and only now have reconstructions of this animal shed light on what it actually looked like (we think). Spinosaurus was discovered in the Sahara desert back in 1912, ten years after the discovery of T-Rex, by a German paleontologist named Ernst Strohmer. He brought home from Egypt a series of high-spined vertebrae, some reaching 5 feet in height, and these were put on display in the Bavarian State Collection of Paleontology in Munich, alongside his other discoveries. Flash forward to April 1944, and an allied bombing campaign destroys the building, as well as all of Strohmer’s fossils.


40 years later, Baryonyx was discovered in England, and helped paleontologists understand a little more about what Spinosaurus would have looked like. By then, remains in Egypt had included huge claws and part of a lower jawbone. Putting them side by side, it showed that Baryonyx was most likely the same type of dinosaur, and it would take 2 more discoveries to cement this into fact, rather than theory.

The claw what snagged me


Irritator was discovered by accident. A British scientist was called up one day by a fossil seller in Brazil, who told him he had some very interesting pterosaur remains for sale. The scientist went to Brazil and made a startling discovery: Not only were the remains altered by the seller with plaster of paris, they weren’t the remains of a ptero at all. They were the remains of a dinosaur very similar to Baryonyx! Named Irritator, after the overall irritating experience of being nearly duped by a greedy fossil seller, it became the 3rd Spinosaur found.

Suchomimus was discovered in 1998 in the country of Niger, in Africa. It had a smaller ridge along its spine, almost like it was trying to grow a sail. Some scientists believe that Suchomimus may actually have been an African sub-species of Baryonyx, and possibly a juvenile. If that proves to be the case, then it may have grown much larger, possibly even rivalling Spinosaurus!

1. Megaraptor Namunhuaiquii

As threats go, this dino was the real-life Indoraptor! It was found in Argentina, and was originally thought to be a massive species of dromaeosaurid. But when more complete remains were unearthed, the huge 1-foot long claws turned out to not be on the second toes, but on the hands!

Reconstructions of this creature show it to be front-heavy, and had a longer torso than most other theropods. It most likely could walk along on all fours, but could also run on its hind legs. The skull also showed that this was a further evolution of the indomitable Allosaur family, which had survived into the Cretaceous, with species ranging from Carcharodontosaurus, Giganotosaurus, Tyrannotitan, and even a species of pygmy Allosaur that lived in the South Polar regions!

It was definitely the stuff of nightmares, and quite possibly the inspiration for one of Jurassic World’s most threatening hybrid creations.

So as you wander the streets tonight, on this night - the scariest night of the year, be on the lookout! These animals may not be around in the flesh any longer, but their ghosts still wander among us. Who knows? One might be right behind you this very moment, just waiting for the perfect moment to strike…

Happy Halloween from the team at the DPGPRC!!


Zuul will destroy your shins!

Zuul probably shattered more Rex shinbones than we know…

Size-wise, it was only as big as a farm tractor. Most other ankylosaurs were about the size of an SUV, or a bit larger.